Such electrode leads, which are used to transmit (e.g., stimulation impulses from cardiac pacemakers to the heart, or possibly action potentials that occur at the heart to the cardiac pacemaker, or the shock impulses of an implanted cardioverter to the heart, and possibly action potentials tapped at the heart to the cardioverter, or which are used to stimulate regions of the brain or nerves, or to transmit electrical signals tapped at the brain/nerve regions to a detection and evaluation device, are used on a large scale for clinical applications.
Of the numerous fields of application for electrode leads, there are a few in which they are exposed, at least in subsections, to high mechanical loads which can impair the functionality or even disable the electrode lead entirely during long-term use. Examples thereof include, but are not limited to, cardiac pacemaker electrode leads, one or more supply leads between an implanted control device and one or more implantable sensors, and ICD electrodes that have one or more very large areas for the application of very high current pulses into the tissue over a large surface area.
First, excess length of the electrode is enclosed in the pacemaker pocket. A tenacious connective-tissue membrane grows around the structure. At the points at which the electrode comes in contact with the housing or intersects other electrode sections, high pressure loads can be placed on the lead body since the connective tissue growing around it does not allow the electrode to yield. Proceeding there from, the electrode extends generally through the region between the clavicle and the first coastal arch. If the electrode is in an unfavorable position, it can become pinched.
Extensive developmental work in the past resulted in various possible solutions to this problem. Electrode leads are designed to be highly flexible. The hard materials, such as, for example, metal, that are used for the supply leads are configured to be highly flexible. Wires are wound into coils or are woven very thinly to form ropes. Plastics that are soft and as elastic as possible are used as insulators that offer the least possible resistance to the movements of the electrode.
The known solutions have not proven to be entirely satisfactory in practice. For example, if radial pressure is applied, the insulation material yields in a manner such that the pressure ultimately acts on the supply leads. Moreover, the pinching of the insulation material stresses the plastic. The stress can cause the material to degrade or directly cause it to yield mechanically. The insulation wears off, bursts, or degrades. Initially, the insulation is breached. Bodily fluid can penetrate the electrode and close electrolyte bridges between the leads. Shunts or short circuits can negatively affect therapy. In the worst case, however, the supply leads break and therapy fails. Furthermore, it can not be ruled out that a broken electrode body will cause further damage.
The problems addressed by the present description are therefore that of providing an improved electrode lead which is more resistant to substantially radially acting forces and friction, at least in certain sections in particular, while remaining as flexible as necessary.
The present inventive disclosure is directed toward overcoming one or more of the above-identified problems.